I'm thinking of getting some Downey shackles along with the OME N85 shocks in the rear to lift my truck. I am wondering a few things about the shackles. First what is the major difference between the HD shackles and the Rubicons. I am someone who uses the truck mostly on a lot of back/ really bumpy roads and moderate wheeling (no rock climbing) Also, do shackles retain the stock ride? Wondering about durability and how they effect the rest of the truck. And finally . . . I know tail pipe modification is involved and am wondering if that is a pain or just a simple adjustment. Thanks.